Oops: general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f] CPU: 1 UID: 0 PID: 26386 Comm: syz.0.8626 Not tainted 6.16.0-rc4-syzkaller-00108-g17bbde2e1716 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__list_del_entry_valid_or_report+0x25/0x190 lib/list_debug.c:49 Code: 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 df eb 5b fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc9000f7fef80 EFLAGS: 00010202 RAX: 000000000000000b RBX: 0000000000000050 RCX: 0000000000080000 RDX: ffffc90004a31000 RSI: 0000000000000b40 RDI: 0000000000000058 RBP: dffffc0000000000 R08: ffff88802f059e00 R09: 0000000000000002 R10: 00000000ffffffff R11: ffffffff897ef160 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000050 R15: ffff888058964000 FS: 0000000000000000(0000) GS:ffff888125d50000(0063) knlGS:00000000f505eb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000003001cff8 CR3: 0000000058274000 CR4: 00000000003526f0 Call Trace: __list_del_entry_valid include/linux/list.h:124 [inline] __list_del_entry include/linux/list.h:215 [inline] list_del_init include/linux/list.h:287 [inline] drr_qlen_notify+0x2c/0xf0 net/sched/sch_drr.c:238 qdisc_tree_reduce_backlog+0x299/0x480 net/sched/sch_api.c:811 fq_change+0x1519/0x1f50 net/sched/sch_fq.c:1147 fq_init+0x699/0x960 net/sched/sch_fq.c:1201 qdisc_create+0x7a9/0xea0 net/sched/sch_api.c:1324 __tc_modify_qdisc net/sched/sch_api.c:1749 [inline] tc_modify_qdisc+0x1426/0x2010 net/sched/sch_api.c:1813 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6953 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg+0x164/0x220 net/socket.c:2652 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf706e539 Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f505e55c EFLAGS: 00000206 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000280 RDX: 0000000000004000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_del_entry_valid_or_report+0x25/0x190 lib/list_debug.c:49 Code: 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 df eb 5b fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc9000f7fef80 EFLAGS: 00010202 RAX: 000000000000000b RBX: 0000000000000050 RCX: 0000000000080000 RDX: ffffc90004a31000 RSI: 0000000000000b40 RDI: 0000000000000058 RBP: dffffc0000000000 R08: ffff88802f059e00 R09: 0000000000000002 R10: 00000000ffffffff R11: ffffffff897ef160 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000050 R15: ffff888058964000 FS: 0000000000000000(0000) GS:ffff888125d50000(0063) knlGS:00000000f505eb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000003001cff8 CR3: 0000000058274000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: f3 0f 1e fa endbr64 9: 41 57 push %r15 b: 41 56 push %r14 d: 41 55 push %r13 f: 41 54 push %r12 11: 53 push %rbx 12: 48 89 fb mov %rdi,%rbx 15: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13 1c: fc ff df 1f: 48 83 c7 08 add $0x8,%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 05 je 0x36 31: e8 df eb 5b fd call 0xfd5bec15 36: 4c 8b 7b 08 mov 0x8(%rbx),%r15 3a: 48 89 d8 mov %rbx,%rax 3d: 48 rex.W 3e: c1 .byte 0xc1 3f: e8 .byte 0xe8